70mm or 75mm MAS

[raginraj]

If I have the extra $20 to get the 75m Pro-M MAS is there any reason I should still go with the 70mm? I have a K&N conical filter so it's either part #ZD5601 or #ZD5602 off ExplorerExpress.com. Basically I just wanted to get a couple opinions before I ordered anything.

Also, I'm definately looking at the BBK 66mm throttle body. How hard and long is the install on this part?

~Thanx

 

[racebronco2]

if you are stock you won't need anything bigger than 70mm ... if you plan on forced induction then the 75 mm would be better

 

[karl_burns]

The factory MAF is actually 70mm in diameter, but the electronics are not calibrated for that amount of air so the fuel addition is calculated differently. Unless you're going to supercharge, the aftermarket 70mm MAF is just fine.
The TB is an hour install at most. Very easy, just remove the plastic cover, unbolt the TB and unhook the accelerator cable. After re-installing, don't forget to have the egine running while adjusting the hard stop screw so that your idle isn't out of whack. It's all listed in the instructions.
Already got your exhaust done? Clean out the entire intake since you're replacing some important parts. Also, do you have an open filament? And you can fab up a 3" intake so there's no constriction from air filter to TB.
Karl